Update style attribute behavior for better object support (#7542)

.changeset/giant-crews-tell.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fix bug when using `define:vars` with a `style` object

packages/astro/package.json

@@ -113,7 +113,7 @@
     "test:e2e:match": "playwright test -g"
   },
   "dependencies": {
-    "@astrojs/compiler": "^1.5.0",
+    "@astrojs/compiler": "^1.5.3",
     "@astrojs/internal-helpers": "^0.1.1",
     "@astrojs/language-server": "^1.0.0",
     "@astrojs/markdown-remark": "^2.2.1",

packages/astro/src/runtime/server/render/util.ts

@@ -90,8 +90,13 @@ Make sure to use the static attribute syntax (\`${key}={value}\`) instead of the
 	}
 
 	// support object styles for better JSX compat
-	if (key === 'style' && !(value instanceof HTMLString) && typeof value === 'object') {
-		return markHTMLString(` ${key}="${toAttributeString(toStyleString(value), shouldEscape)}"`);
+	if (key === 'style' && !(value instanceof HTMLString)) {
+		if (Array.isArray(value) && value.length === 2) {
+			return markHTMLString(` ${key}="${toAttributeString(`${toStyleString(value[0])};${value[1]}`, shouldEscape)}"`);
+		}
+		if (typeof value === 'object') {
+			return markHTMLString(` ${key}="${toAttributeString(toStyleString(value), shouldEscape)}"`);
+		}
 	}
 
 	// support `className` for better JSX compat

packages/astro/test/astro-directives.test.js

@@ -53,6 +53,17 @@ describe('Directives', async () => {
 		expect($('h1').attr('style').toString()).to.include('--textColor: red;');
 	});
 
+	it('Properly handles define:vars on style elements with style object', async () => {
+		const html = await fixture.readFile('/define-vars/index.html');
+		const $ = cheerio.load(html);
+
+		// All styles should be bundled
+		expect($('style')).to.have.lengthOf(0);
+
+		// Inject style attribute on top-level element in page
+		expect($('#compound-style').attr('style').toString()).to.include('color:var(--fg);--fg: black;--bg: white;');
+	});
+
 	it('set:html', async () => {
 		const html = await fixture.readFile('/set-html/index.html');
 		const $ = cheerio.load(html);

packages/astro/test/fixtures/astro-directives/src/pages/define-vars.astro

@@ -36,7 +36,7 @@ let undef: undefined;
 		<script id="inline-5" define:vars={{ undef }}>
 			console.log(undef);
 		</script>
-
+    <div id="compound-style" style={{ color: `var(--fg)` }}></div>
 		<Title />
   </body>
 </html>